title: Optimization of molecular distillation to concentrate ethyl esters of eicosapentaenoic (20:5 ω-3) and docosahexaenoic acids (22:6 ω-3) using simplified phenomenological modeling.
abstract: BACKGROUND
  Squid oil contains high concentration of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The purpose of this work was to optimize the process of separation by molecular distillation of ω-3 fatty acid ethyl esters obtained from squid oil. The separation process was conducted in two stages in a laboratory-scale molecular distiller. A mathematical model based on the mass transfer phenomena was developed. The Nelder-Mead numerical method was used to optimize the model.
  
  
  RESULTS
  The ω-3 content in the output material of the stage II increased with the temperature of stage I (T¹). The amount of distillated material in stage I increased and the distillated material in the stage II decreased with the increment of T¹. That implied a decreasing of the ω-3 recovery in the distillated material in the stage II. In addition, the ω-3 recovery increased with the temperature of stage II (T²), but the temperatures should be less than 140 °C to avoid chemical changes. The optimization results showed an optimal process at T¹ = 120.5 °C and T² = 140 °C.
  
  
  CONCLUSIONS
  The theoretical model and the optimization give decision criteria about the operative conditions for reaching the highest yield during molecular distillation of ω-3 fatty acid ethyl esters.
authors.affiliation: Facultad de Ingeniería, Universidad Nacional de Río Cuarto, Ruta 36 Km 601, 5800 Río Cuarto, Córdoba, Argentina. prossi@ing.unrc.edu.ar
authors.forename: Pablo C
authors.initials: PC
authors.lastname: Rossi
authors.forename: María del C
authors.initials: Mdel C
authors.lastname: Pramparo
authors.forename: María C
authors.initials: MC
authors.lastname: Gaich
authors.forename: Nelson R
authors.initials: NR
authors.lastname: Grosso
authors.forename: Valeria
authors.initials: V
authors.lastname: Nepote
mesh_terms: D000818:Animals; D049832:Decapodiformes; D057168:Distillation / Q000379:methods*; D004281:Docosahexaenoic Acids; D015118:Eicosapentaenoic Acid; D004952:Esters; D005395:Fish Oils; D008962:Models, Theoretical
chemical_list: D004952:Esters; D005395:Fish Oils; D004281:Docosahexaenoic Acids; D015118:Eicosapentaenoic Acid